The Pipeline and Hazardous Materials Safety Administration said Tuesday it proposed fining three companies involved in the shipments a total of $93,000. The trucks were taking oil to be loaded into rail tank cars.

A runaway oil train derailed and exploded in the downtown area of Lac-Megantic, Quebec, near the Maine border, in July. Forty-seven people were killed and 30 buildings destroyed.

The accident was a wake-up call for safety officials who were surprised by the severity of the accident. Tests of Bakken oil show it is more volatile than other types of crude.